Lib/test/test_fileinput.py

   1 '''
   2 Tests for fileinput module.
   3 Nick Mathewson
   4 '''
   5
   6 from test_support import verify, verbose, TESTFN
   7 import sys, os, re
   8 from StringIO import StringIO
   9 from fileinput import FileInput
  10
  11 # The fileinput module has 2 interfaces: the FileInput class which does
  12 # all the work, and a few functions (input, etc.) that use a global _state
  13 # variable.  We only test the FileInput class, since the other functions
  14 # only provide a thin facade over FileInput.
  15
  16 # Write lines (a list of lines) to temp file number i, and return the
  17 # temp file's name.
  18 def writeTmp(i, lines):
  19     name = TESTFN + str(i)
  20     f = open(name, 'w')
  21     f.writelines(lines)
  22     f.close()
  23     return name
  24
  25 pat = re.compile(r'LINE (\d+) OF FILE (\d+)')
  26
  27 def remove_tempfiles(*names):
  28     for name in names:
  29         try:
  30             os.unlink(name)
  31         except:
  32             pass
  33
  34 def runTests(t1, t2, t3, t4, bs=0, round=0):
  35     start = 1 + round*6
  36     if verbose:
  37         print '%s. Simple iteration (bs=%s)' % (start+0, bs)
  38     fi = FileInput(files=(t1, t2, t3, t4), bufsize=bs)
  39     lines = list(fi)
  40     fi.close()
  41     verify(len(lines) == 31)
  42     verify(lines[4] == 'Line 5 of file 1\n')
  43     verify(lines[30] == 'Line 1 of file 4\n')
  44     verify(fi.lineno() == 31)
  45     verify(fi.filename() == t4)
  46
  47     if verbose:
  48         print '%s. Status variables (bs=%s)' % (start+1, bs)
  49     fi = FileInput(files=(t1, t2, t3, t4), bufsize=bs)
  50     s = "x"
  51     while s and s != 'Line 6 of file 2\n':
  52         s = fi.readline()
  53     verify(fi.filename() == t2)
  54     verify(fi.lineno() == 21)
  55     verify(fi.filelineno() == 6)
  56     verify(not fi.isfirstline())
  57     verify(not fi.isstdin())
  58
  59     if verbose:
  60         print '%s. Nextfile (bs=%s)' % (start+2, bs)
  61     fi.nextfile()
  62     verify(fi.readline() == 'Line 1 of file 3\n')
  63     verify(fi.lineno() == 22)
  64     fi.close()
  65
  66     if verbose:
  67         print '%s. Stdin (bs=%s)' % (start+3, bs)
  68     fi = FileInput(files=(t1, t2, t3, t4, '-'), bufsize=bs)
  69     savestdin = sys.stdin
  70     try:
  71         sys.stdin = StringIO("Line 1 of stdin\nLine 2 of stdin\n")
  72         lines = list(fi)
  73         verify(len(lines) == 33)
  74         verify(lines[32] == 'Line 2 of stdin\n')
  75         verify(fi.filename() == '<stdin>')
  76         fi.nextfile()
  77     finally:
  78         sys.stdin = savestdin
  79
  80     if verbose:
  81         print '%s. Boundary conditions (bs=%s)' % (start+4, bs)
  82     fi = FileInput(files=(t1, t2, t3, t4), bufsize=bs)
  83     verify(fi.lineno() == 0)
  84     verify(fi.filename() == None)
  85     fi.nextfile()
  86     verify(fi.lineno() == 0)
  87     verify(fi.filename() == None)
  88
  89     if verbose:
  90         print '%s. Inplace (bs=%s)' % (start+5, bs)
  91     savestdout = sys.stdout
  92     try:
  93         fi = FileInput(files=(t1, t2, t3, t4), inplace=1, bufsize=bs)
  94         for line in fi:
  95             line = line[:-1].upper()
  96             print line
  97         fi.close()
  98     finally:
  99         sys.stdout = savestdout
 100
 101     fi = FileInput(files=(t1, t2, t3, t4), bufsize=bs)
 102     for line in fi:
 103         verify(line[-1] == '\n')
 104         m = pat.match(line[:-1])
 105         verify(m != None)
 106         verify(int(m.group(1)) == fi.filelineno())
 107     fi.close()
 108
 109
 110 def writeFiles():
 111     global t1, t2, t3, t4
 112     t1 = writeTmp(1, ["Line %s of file 1\n" % (i+1) for i in range(15)])
 113     t2 = writeTmp(2, ["Line %s of file 2\n" % (i+1) for i in range(10)])
 114     t3 = writeTmp(3, ["Line %s of file 3\n" % (i+1) for i in range(5)])
 115     t4 = writeTmp(4, ["Line %s of file 4\n" % (i+1) for i in range(1)])
 116
 117 # First, run the tests with default and teeny buffer size.
 118 for round, bs in (0, 0), (1, 30):
 119     try:
 120         writeFiles()
 121         runTests(t1, t2, t3, t4, bs, round)
 122     finally:
 123         remove_tempfiles(t1, t2, t3, t4)
 124
 125 # Next, check for proper behavior with 0-byte files.
 126 if verbose:
 127     print "13. 0-byte files"
 128 try:
 129     t1 = writeTmp(1, [""])
 130     t2 = writeTmp(2, [""])
 131     t3 = writeTmp(3, ["The only line there is.\n"])
 132     t4 = writeTmp(4, [""])
 133     fi = FileInput(files=(t1, t2, t3, t4))
 134     line = fi.readline()
 135     verify(line == 'The only line there is.\n')
 136     verify(fi.lineno() == 1)
 137     verify(fi.filelineno() == 1)
 138     verify(fi.filename() == t3)
 139     line = fi.readline()
 140     verify(not line)
 141     verify(fi.lineno() == 1)
 142     verify(fi.filelineno() == 0)
 143     verify(fi.filename() == t4)
 144     fi.close()
 145 finally:
 146     remove_tempfiles(t1, t2, t3, t4)
 147
 148 if verbose:
 149     print "14. Files that don't end with newline"
 150 try:
 151     t1 = writeTmp(1, ["A\nB\nC"])
 152     t2 = writeTmp(2, ["D\nE\nF"])
 153     fi = FileInput(files=(t1, t2))
 154     lines = list(fi)
 155     verify(lines == ["A\n", "B\n", "C", "D\n", "E\n", "F"])
 156     verify(fi.filelineno() == 3)
 157     verify(fi.lineno() == 6)
 158 finally:
 159     remove_tempfiles(t1, t2)